1. Field of the Invention
This invention relates generally to an apparatus and method for voice actuating a radio transmitter and in particular to an apparatus and method for utilizing a contact vibration transducer for transducing the voice information.
2. Description of the Prior Art
Recent advances in the state of the art in mobile radios have enabled these time-saving devices to be utilized on a variety of different mobile vehicles. As the use of the two-way radios has become more common, businessmen and sportsmen have become more dependent upon the communications services provided by the equipment. As a result, considerable effort is now being expended to improve the efficiency of the communications process which will ultimately result in a more efficient utilization of the communications resources.
Two-way communications radios have long been used on motorcycles by public service organizations such as police, fire, etc. These two-way mobile communications transceivers generally utilize a push-to-talk system which is actuated by depressing a button on the microphone. However, this push-to-talk system has proven to be unsatisfactory for several reasons. First, the operator must grasp the microphone and the push-to-talk switch in one hand, which can be dangerous when driving the motorcycle, or other similar vehicle, during heavy or congested traffic. Other radio services have adopted a voice actuated transmit system (VOX) for keying the transmitter responsive to the voice of the operator. However, this system is not adaptable to use on motorcycles or in areas of high ambient noise levels since the unwanted noise often causes a false keying of the transmitter. Secondly, since the microphone is equally responsive to voice and noise sources, the intelligibility of the operator's voice is generally impaired due to the noise contributed by the wind or the ambient noise sources.
The prior art does not lend any useful suggestions to these problems. Cribb, in U.S. Pat. No. 3,588,359, discloses a voice operated transceiver designed to be incorporated into a protective suit. Miyachi, in U.S. Pat. No. 3,944,924, discloses a Citizens Band radio transceiver for being mounted on a motorcycle. The transceiver utilizes a standard audio type microphone transducer which is mounted upon the helmet for being located near the communicator's mouth. No automatic voice operation is provided. Van Gastle, in U.S. Pat. No. 2,490,563, discloses a system for mounting a radio upon the handle bars of motorcycles or other vehicles. Goldfus, in U.S. Pat. No. 2,980,379, discloses a detachable rack for coupling a portable radio to a mobile vehicle. Wertheimir, in U.S. Pat. No. 3,134,945, discloses a portable radio which may be used with a motor vehicle or may be detached and used as a portable radio with its self-contained power supply.